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Dell OptiPlex GXa won't boot; how to configure devices in SCSI BIOS

The computer now stops in booting right after it shows the BIOS logo and brand. It doesn’t even do a memory count. :( The SCSI card is not connected at all.
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Addendum: It does give the prompt to enter the BIOS, and I can get in there and change stuff, but the booting doesn't advance any further except to say "Diskette drive 1 seek failure." Oh, joy.

I got one of those PCI/ISA diagnostic cards from eBay. Upon reaching this point in the boot, it gives code E0. It gives many others during between reset and then, but I don't know if those are errors or normal processes. I'd have to take a slow-motion video to list them all. This is my first time using this diagnostic card.
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I didn't need the diagnostic card. I'm not quite sure why it was giving me trouble booting, but I got it to work.

I had the 3.5-inch floppy B-drive disconnected and set as "None" in the BIOS, because I was using that power plug to power a CF card adaptor. When I got a Molex-to-Berg adaptor so I could power both the 3.5-inch floppy and the CF card adaptor, and set the B-drive in the BIOS again, it worked. I also was trying to have a physical hard drive connected on the secondary IDE channel. I had to try several hard drives before I found a working one (as in, the others I tried are bad, I guess) but once I got a good IDE HDD, now all drives are recognized and working: A, B, the C-drive on the CF card, the physical IDE HDD as drive D; and drives E, F, and G on the CF card. So now I am finally ready to use this computer to inspect and copy off a big tote of vintage IDE hard drives.

But, I will still have to come back to working on this computer at some time, since I do want to get the SCSI CD-ROM drive operational, and be able to connect whatever else SCSI that I want.
 
Returning to this computer. Using Ontrack Disk Manager for DOS, I was able to have DOS access all 16 GB. of the CF card (by default MS-DOS 6.22 can only see 8.4 GB. on a drive), divided into 2 GB. drives. Using the last drive of the CF card, I copied the Win98 SE installation CD files onto it. I was thus able to install Windows 98 onto the CF card. That enables a lot of automatic driver installation, long file name access, far easier file management, etc. The IDE channels are working fine.

The Adaptec SCSI card is still not working. Despite once recognizing a (faulty) hard drive and the CD-ROM drive, it will still recognize neither now.
  • I found the installation guide for the card (in addition to the user's reference manual I found earlier), but that does not help.
  • The card has a J4 jumper (set to 0) and a J6 jumper (set to 0). Neither its manual nor installation guide tell what these jumpers are for. Can anyone help identify them? Maybe they are the answer.
Dell ISA configuration utility
This webpage of the manual for the GX1 says:
NOTICE: The ICU is intended only for configuring non-Plug and Play ISA expansion cards. It should not be used for assigning resources to Plug and Play expansion cards and PCI expansion cards. These cards should be configured automatically by the basic input/output system (BIOS).
So the Dell ISA configuration utility is not the solution for this PCI SCSI card.

More efforts:
  • A new-used 68-pin SCSI HDD (18 GB.) arrived via eBay today. The listing said it works. I connected it with the 50-68-80-pin SCSI adaptor (with Molex connector for power). It sounds fine when powered up. The SCSI BIOS does not see it.
  • I had Win98 search for new hardware; none found.
  • Using Control Panel/Add New Hardware, I specifically told Win98 to install drivers for this model of SCSI card. It did; nothing changed even after reboot.
The SCSI card BIOS is always announced on the ASCII BIOS screen. When the SCSI card has worked in the past and recognized devices, it then listed them on the ASCII boot-up screen.

I tried EZ-SCSI 4.0a for 1.44 MB. floppy. It said no SCSI host adapters were detected and wouldn't proceed any further than that. I went into the SCSI BIOS and verified that the host adapter was in fact enabled.

So the problem seems to clearly be the SCSI card somehow. It can interact with the motherboard and recognizes itself but doesn't recognize any other SCSI devices connected to it, even though it once did. I don't know what setting I might need to change.

The card has a J4 jumper (set to 0) and a J6 jumper (set to 0). Neither its manual nor installation guide tell what these jumpers are for. Can anyone help identify them? Maybe they are the answer. J4 seems to be labeled LVDTE and J6 seems to be labeled SETE. But I've also looked at 5 other copies of this model SCSI card on eBay and none of them have jumpers on either of those positions.
 

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TE probably means Termination Enabled, SE for Single ended and LVD for Low Voltage Differential.
But what do those things mean? And are they relevant to the SCSI card not seeing devices?

If I have IDE hard drives (or the CF card) attached along with a SCSI HDD, would that cause any conflict?

Errata: J4 looks like it's labeled LVOTE, not LVDTE.
 
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It's LVDTE = "low voltage differential termination enable" Neither J4 nor J6 should have a jumper. Your CD-ROM drives (which you should start with) are SE (single-ended). When you get those working, we'll move to the hard drive. Please note that there is 8 bit and 16 bit single-ended and then there is LVD (low-voltage differential) and HVD (high-voltage differential). Generally, you only see HVD on very old SCSI gear.
 
The SCSI card is getting closer.

No devices are "formally" recognized by the SCSI card in its BIOS. Yet, with all the SCSI BIOS settings set to default, the computer will boot to the new-used SCSI HDD (18 GB.), but only if the CF card is not plugged in.

The new-used SCSI HDD (18 GB.) is itself working fine. It came with Win95 on it.

If I have the CF card plugged in, then the computer boots to the CF card and does not see the SCSI HDD.

Does that give any feedback on what settings/configuration I should be using to formally have the SCSI card see the SCSI devices? There is a setting in the SCSI BIOS of which SCSI device number and LUN number to boot from. It is set to 0, 0, which I think directs it to the SCSI HDD. Is that why I can't get the SCSI devices to be seen formally? If so, what do I change that to to disable it?
 
Your CD-ROM drives (which you should start with) are SE (single-ended). When you get those working, we'll move to the hard drive.
Sorry for the plot twist for you. :sneaky: The SCSI HDD is already halfway working, while the SCSI CD-ROM is not.

What does single-ended mean? Does it need a terminator on the end of that SCSI cable? If so, the end of it is actually an open SCSI port on a backplate.
 
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If you don't want the system to boot from the SCSI HD, change its ID to something other than 0, 1 or 7. The Aadaptec BIOS is set by default to check only for IDs 0 or 1 for a boot device.
 
I set the SCSI HDD to device #4. No change as far as the SCSI card formally recognizing anything.

Okay, let's start with the SCSI CD-ROM drive on the SCSI single-ended channel. Its jumpers have it set as SCSI device 3; that has never changed. What does single-ended mean? Does it need a terminator on the end of that SCSI cable? If so, the end of it is actually an open SCSI port on a backplate.
 
Changed SCSI HDD to device #2. That puts it ahead of the CD-ROM drive, device #3.

I notice that when I do a device scan via “SCSI Disk Utilities” in the SCSI BIOS, the CD-ROM starts to spin up (that has always happened). So the SCSI card seems like it’s just on the verge of being able to formally recognize the devices.

Attached are some screenshots of the SCSI BIOS menus. I can list out all the possible options for everything if needed.

This page was almost the exact thing I needed. I mean, it told me exactly what to change, but so far, it hasn't worked.
 

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SE: single-ended. Signals are referenced to a common ground (like most TTL logic). SE Wiki
Differential: Signals are sent over pairs of wires, one pair per signal, with no common return (ground). LVDS Wiki.

Re: termination. Termination is required on both types of signalling, with termination at both ends--and none required in the middle. For example:

Controller-->Device

Both the controller and device must be terminated.

Device1->Controller->Device2

Device1 and Device2 require termination, but the controller does not.

Controller->Device1->Device2

The controller and Device2 require termination, but Device1 does not.
 
Termination is required on both types of signalling, with termination at both ends--and none required in the middle.
Would termination be required on the end of the SE channel whose last connector is on the backplate and is not terminated? Or, if a terminator is required, could it be on the CD-ROM drive?

Addendum: The jumper pins on the back of the CD-ROM drive have an option for TERM, so I will find a jumper and put it on there.
 
Backplate of the controller? It's terminated internally.

One of the features of the AHA-29160 BIOS is that it puts up a warning message if it detects improper or missing termination. Very handy.
 
The SE channel for the CD-ROM ends at a breakout backplate. That is separate from the SCSI card backplate.

Can a computer of this era use IDE and SCSI simultaneously, or have I unknowingly been causing a conflict by that the whole time?
 
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In theory, yes you can use both. HOWEVER--make sure that you don't have a tug-of-war between BIOSes. For example, setting a disk ID of 0 or 1 on most adaptec cards indicates that you want to use the disk as a boot device. Generally, since the SCSI BIOS is usually the "last in", this will pre-empt any IDE selection.
That's not to say that there might not be exceptions. For example, I've got a couple of motherboards here where the support for the Adaptec 29xx card is built into the main BIOS.
 
Is the SE channel terminated, or do I have to terminate it? If I have to terminate it, can I terminate it at the CD-ROM terminator jumper, or do I have to add a terminator to the breakout backplate? (I had to order jumpers from eBay last night since I didn’t have any spares to use.)

Looking at the screenshots I made in post #71, what settings should I try?
 
Well, I got a 213 MB. SCSI 50-pin HDD (Conner CP30200) in the mail yesterday from eBay for another vintage computer, and I tried it out on the GXa. The card still doesn't recognize devices when scanning.

I put the 213 MB. drive in the intended computer, a 1996 Compaq Prosignia, and the drive works fine.

I'm inclined at this moment to assume the SCSI card is the problem. So I ordered a replacement SCSI card of the same model from eBay. Not expensive. Even if I do end up getting this first SCSI card to work, I'll have the second one as a card I can have in another unit. When it arrives, it should allow me to reasonably conclude whether the problem is the SCSI card or not. If the SCSI card is not the problem, and the drives are not the problem, and the cables are not the problem, then the problem has to be the SCSI settings.

So close. So close. I will have an operational high-profile OptiPlex ultimate vintage gaming computer, equipped the way I want it to be. I will.
 
The second SCSI card arrived today, after a long wait. It is the same model. The SCSI BIOS works fine, and it scans for SCSI devices fine; it recognized the CD-ROM drive with no trouble at all. I plugged in the CD-ROM drive as SCSI device #3. The SCSI card is device #7. The boot sequence goes as expected, until it gets to the point where (because it can't see the expected IDE hard drives since they are disconnected) it asks me to press F1 to continue boot or F2 to enter the system BIOS. Whether I press F1 or F2 doesn't matter; the computer does nothing further no matter what I press, not even Ctrl-Alt-Del. Now what? Does anyone have any explanation of what the SCSI card is trying to do that is getting "interference" and making it hang up?
 
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I have concluded (with inexhaustive empirical evidence, and without definite proof) that IDE and SCSI are incompatible to use simultaneously in this computer. Therefore I have removed all the SCSI hardware. I need the IDE channels to be usable so that I can examine hard drives I have salvaged.

That means that IDE channel 1 will be a new-to-this-computer HDD and an IDE CD-ROM drive I will get from my inventory. Channel 2 will likely have to be dedicated to just the CF card adaptor, since those are known to be territorial like that, despite having jumpers to not take up the whole channel. Or I may be able to use a native USB port for a multi-card reader.

So far the IDE channels have been unable to recognize IDE HDDs greater than or equal to 160 GB. It may be that the few IDE HDDs I have that are that big are simply bad. I will try the remainder of the ones I have that are that big and step downward in size until I find the biggest size the computer can accommodate.

I guess this brings this thread to a close. I need to move on to examine and get these HDDs out of my computer room.
 
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